Joint road toll pricing and capacity development in discrete transport network design problem

The paper demonstrates a method to determine road network improvements that also involve the use of a road toll charge, taking the perspective of the government or authority. A general discrete network design problem with a road toll pricing scheme, to minimize the total travel time under a budget constraint, is proposed. This approach is taken in order to determine the appropriate level of road toll pricing whilst simultaneously addressing the need for capacity. The proposed approach is formulated as a bi-level programming problem. The optimal road capacity improvement and toll level scheme is investigated with respect to the available budget levels and toll revenues.     

Examining the effect of life course events on modality type and the moderating influence of life stage

Transportation - Previous research has demonstrated the relevance of life events to explain changes in travel behavior. Less clear is the moderating role played by life stages on the relationship...     

Virtual reality simulation game approach to investigate transport adaptive capacity for peak oil planning

The peak and decline of world oil production is an emerging issue for transportation and urban planners. Peak oil from an energy perspective means that there will be progressively less fuel. Our work treats changes in oil supply as a risk to transport activity systems. A virtual reality survey method, based on the sim game concept, has been developed to audit the participant’s normal weekly travel activity, and to explore participant’s travel adaptive capacity. The travel adaptive capacity assessment (TACA) Sim survey uses avatars, Google Map™, 2D scenes, interactive screens and feedback scores. Travel adaptive capacity is proposed as a measure of long-range resilience of activity systems to fuel supply decline. Mode adaptive potential is proposed as an indicator of the future demand growth for less energy intensive travel. Both adaptation indicators can be used for peak oil vulnerability assessment. A case study was conducted involving 90 participants in Christchurch New Zealand. All of the participants were students, general staff or academics at the University of Canterbury. The adaptive capacity was assessed by both simulated extreme fuel price shock and by asking, “do you have an alternative mode?” without price pressure. The travel adaptive capacity in number of kilometers was 75% under a 5-fold fuel price increase. The mode adaptive potential was 33% cycling, 21% walking and 22% bus. Academics had adaptive capacity of only 1-5% of trips by canceling or carrying out their activity from home compared to 10-18% for students.     

Community Participation in Marine Protected Area Management: Wakatobi National Park,Sulawesi, Indonesia

Coral reef areas are threatened worldwide by growing populations, tourism development, and use of poison and dynamite in fishing in areas adjacent to the reefs. The designation of marine protected areas is one strategy for addressing these problems. Wakatobi National Park, established in Eastern Indonesia in 1996, contains approximately 50,000 ha of coral reefs and a resident population of Sama-Bajo people whose traditions and current livelihoods tie them closely to the sea. The present research, using participatory rural appraisal methods, focused upon the impact of the designation of the Marine Park on their lives and investigated the potential for public participation in park planning and management. The Wakatobi Park Management Plan does not address the needs and interests of local people. Priority should be placed on adaptation of park zoning and protection regulations to accommodate the livelihood requirements of indigenous communities.     

Criteria for Evaluating the Design of Implementation Models for Integrated Coastal Management

Despite the emphasis placed on the contextual nature of integrated coastal management (ICM) implementation in the literature, many uniformities are encountered in ICM implementation worldwide. In this article the tangled threads of ICM practice are unravelled and a theoretically founded set of criteria for evaluating the design of ICM implementation models is provided. First, paradigms in integrated environmental management (IEM) implementation, the broader domain within which ICM practice is nested, are characterized in terms of their key concepts. Next, the paradigms are used as a mechanism to distill uniformities in ICM practice as reported in review articles. Finally a set of fourteen building blocks against which the scientific credibility of contextual, country-specific ICM implementation models can be validated, is generated by translating the theory-based characterization into evaluation criteria readily accessible to practitioners.     

Local shopping as a strategy for reducing automobile travel

Transportation - Suburban development in the US is widely criticized for its contribution to automobile dependence and its consequences. Not surprisingly, then, a return to more urban-style...     

Public private partnerships in transportation: Some insights from the European experience

Most EU member states and the European Commission regard the PPP as an important tool to attract additional financial resources for high priority investments such as transport. The objective of this paper is to delineate the EU panorama of PPP markets and investigate the impacts of EU institutions in the development and success of this type of financial arrangement for the transport sector in Europe. We examine how the scope of the PPP in Europe is based on the flexibility and adaptability of the contract to the features of the project and to the economic and institutional environment. These issues are illustrated through a number of examples in the transport sector. We conclude by observing that the market for PPPs, although still fragmented nationally, is developing a European dimension and attracting resources from a variety of players.     

The undrained bearing capacity of a spudcan foundation under combined loading in soft clay

Mobile jack-up drilling rigs are typically supported by individual, large diameter spudcan foundations. Before deployment, the suitability of a jack-up to a location must be shown in a site-specific assessment under loads associated with a 50-year return period storm, which ultimately need to be resisted by the foundations. The capacity of the spudcans under combined vertical, horizontal and moment loading is therefore integral to the overall site-specific assessment of the jack-up.In soft clays, spudcans can penetrate deeply into the seabed, sometimes up to several footing diameters, with soil flowing around the downward penetrating footing, sealing the cavity. Although this is generally believed to provide some additional bearing capacity to the footing, no detailed study or formal guidance is available to date. This study, therefore, investigates the influence of soil back-flow on the failure mechanisms and quantifies the effect on the capacity of a spudcan under general loading through finite element analyses. A closed-form analytical expression is developed that describes the capacity envelope under combined loading, applicable to embedment depths ranging from shallow to deep.     

The relation between bicycle commuting and non-work cycling: results from a mobility panel

This study aims to establish whether or not bicycle commuting and cycling for other purposes (e.g. shopping, visiting friends) are related over time. Using previously gathered panel data (the Dutch mobility panel) these relationships are revealed by (1) a series of conditional change models and (2) a latent transition model. The conditional change models indicate that, with a lag of 1 year and controlling for a range of background characteristics, bicycle commuting and non-work cycling (in number of weekly trips) have a positive reciprocal influence on each other. The models show that work-related factors, such as the distance to work or whether a person receives a travel allowance, affect not only bicycle commuting but also non-work cycling. The latent transition model indicates that people can be clustered into four groups: non-cyclists, non-work cyclists, all-around cyclists and commuter cyclists. This model shows that people with a consistent propensity to not cycle at all (non-cyclists) or to cycle for both work and non-work purposes (all-around cyclists) are most stable in their travel behavior. Non-work cyclists and commuter cyclists are less stable in travel behavior. The model also shows that all-around cyclists are not (significantly) affected by a change in the distance to work. The article concludes with several directions for future research.     

The Role of Tradable Credit Schemes in Road Traffic Congestion Management

Abstract

Road traffic congestion is not yet reflected in current market prices within the sector and has given rise to a number of instruments to mitigate the resulting negative impacts. The focus of this paper is the tradable credit scheme — an incentive-based economic measure — in order to address traffic congestion. The research questions are (1) whether the state-of-the-art in the literature suggests that tradable credit schemes could be feasibly introduced to mitigate congestion, and (2) whether a tradable credit scheme could have advantages over other instruments. A brief outline of congestion mitigation approaches is provided first to position this type of economic instrument with respect to other measures. The broad issues in the design of a tradable credit scheme are then presented. Most research to date has focused on the use of tradable credits to manage related pollution, but it is clear there is potential to design a scheme for traffic congestion management. To date this is a novel review of tradable credit schemes that has focused specifically on their role in road traffic congestion management.